Intestinal dendritic cells (DCs) send processes between epithelial cells into the gut lumen to sample pathogens. Noninvasive enteropathogenic Escherichia coli (EPEC) colonize the gut using a type three secretion system (T3SS) to inject effector proteins into epithelial cells. We hypothesized that EPEC might also inject proteins into DC processes to dampen immune recognition. Using a T3SS-linked...

Enteropathogenic Escherichia coli (EPEC), a common cause of infant diarrhea, is associated with high risk of mortality in developing countries. The primary niche of infecting EPEC is the apical surface of intestinal epithelial cells. EPEC employs a type three secretion system (TTSS) to inject the host cells with dozens of effector proteins, which facilitate attachment to these cells and success...

We previously reported that enteropathogenic Escherichia coli (EPEC) infection triggered a large release of ATP from the host cell that was correlated with and dependent on EPEC-induced killing of the host cell. We noted, however, that under some circumstances, EPEC-induced ATP release exceeded that which could be accounted for on the basis of host cell killing. For example, EPEC-induced ATP re...

Enteropathogenic Escherichia coli (EPEC) infection of T84 cells induces a decrease in transepithelial resistance, the formation of attaching and effacing (A/E) lesions, and cytokine production. The purpose of this study was to investigate the ability of EPEC to activate mitogen-activated protein (MAP) kinases in T84 cells and to correlate these signaling pathways with EPEC-induced cell response...

Annexin 2 is a Ca2+-regulated membrane- and F-actin-binding protein implicated in the stabilization or regulation of membrane/cytoskeleton contacts, or both, at the plasma membrane and at early endosomal membranes. To analyze the dynamic nature of such action we investigated whether annexin 2 could be found at sites of localized actin rearrangements occurring at the plasma membrane of HeLa cell...

The enteropathogenic Escherichia coli (EPEC) locus of enterocyte effacement (LEE)-encoded effectors EspF and Map are multifunctional and have an impact on the tight junction barrier while the non-LEE-encoded proteins NleH1 and NleH2 possess significant anti-inflammatory activity. In order to address the temporal expression of these important genes in vivo, their promoters were cloned upstream o...

Enteropathogenic Escherichia coli (EPEC) alters many functions of the host intestinal epithelia. Inflammation is initiated by activation of nuclear factor (NF)-kappaB, and paracellular permeability is enhanced via a Ca2+- and myosin light-chain kinase (MLCK)-dependent pathway. The aims of this study were to identify signaling pathways by which EPEC triggers inflammation and to determine whether...

The hallmark of enterohemorrhagic Escherichia coli (EHEC) and enteropathogenic E. coli (EPEC) adhesion to cultured human host cells is intimate attachment and the formation of attaching and effacing (A/E) lesions. Recently, EHEC O157:H7 was shown to induce A/E lesions on human intestinal explants. Unlike EPEC, which colonized the small intestine, EHEC adhesion was restricted to follicle-associa...

The presence of the pathogenicity island (PAI) O122 genes, efa1 (lifA), sen, pagC, nleB, and nleE, in typical and atypical enteropathogenic Escherichia coli (EPEC) strains was investigated. The simultaneous occurrence of all genes was statistically associated with diarrhea due to atypical EPEC. Detection of the complete PAI O122 could aid in the identification of potential pathogenic strains of...

Enterohemorrhagic and enteropathogenic Escherichia coli (EHEC and EPEC, respectively) strains are closely related human pathogens that are responsible for food-borne epidemics in many countries. Integration host factor (IHF) and the locus of enterocyte effacement-encoded regulator (Ler) are needed for the expression of virulence genes in EHEC and EPEC, including the elicitation of actin rearran...